View Full Version : Oil warning when motor is off

07-22-2018, 02:07 AM
Hi all,

Maybe someone can help me with this.

When turn the key in the ignition (not start) the dash gifs me the red oil warning and stays there.
But as i start the engine 1 or 2 secs it goes away and never shows again.

So only when ignition is on i get the warning, while driving never.
Oil level is good

It's a B5 2.6 with the ABC engine

Hope someone knows more

07-23-2018, 12:43 AM
If you mean the dash lights thatís normal. It is just testing they all work. If you mean the lcd display then that isnít normal. Which is it?

Sent from my iPhone using Tapatalk

07-23-2018, 04:21 AM
If it is the giving the actual warning with the beeps and everything, (and not just the bulb check), this is due to the oil pressure switch being faulty or bypassed. Basically, the cluster sees the oil pressure switch is closed (oil pressure is "good") but it also sees that engine RPM is zero. So it instantly knows that is bogus and the oil pressure switch is lying. So you get a warning. Once the engine is started, the pressure switch being closed is plausible (actually required if coolant temp is less than 60C) and the warning is cleared.

So you have a few possibilities (in order of probability, basically):
- Your oil pressure switch is faulty and is stuck in the closed position (as if oil pressure is present at all times)
- Somebody bypassed the oil pressure switch (cut the wire and tied it to chassis ground)
- There is a wiring fault (wire rubbed through and is touching chassis ground somewhere)
- You have some weird failure of the instrument cluster's oil pressure warning circuit (very unlikely)

07-24-2018, 08:49 AM
Thanks for the reply this makes sense.

The warning is on display, it display when the engine is cold (below 60c) and when it's hot (90c)
Iam goning to replace the cluster anyway because of the display (lines not working) can't stand it.

Ill replace the oil pressure switch .. do i need OEM or are 3rd party ok to?

I have the car for 5 years now it has never done this, so no bypass

Wiring fault i don't hope so .. ill check that after none of this above worked.

Stupid question probably .. But is save to drive?

07-24-2018, 10:03 AM
It should be ok, but it is good practice to check the oil pressure (with a mechanical gauge) whenever there is a warning given.

Because the switch is stuck (or the wiring is shorted to ground) you basically have no oil pressure warning system at all. In the present state, if the drain plug were to fall out on the highway at 75 mph, you would receive exactly zero warning on the dashboard. The engine would be junk before you even knew there was a problem. So, its a good idea to check the pressure to be sure (its a good checkup to do anyway), but there is no functioning warning system until you get it fixed. It would be like driving a car with a burnt out oil pressure light bulb. So it's up to you.